Archimedes Principle

Archimedes’ Principle state that “ When an object is immersed in a fluid (a liquid or a gas) ,the buoyant force  
( upthrust force) on the object  is equal  to the weight of fluid displaced by the object.

From  Archimedes’s Principle :

Buoyant Force, Fb  = Weight of fluid displace
            =  mg                 (note : F = ma)
            =  ρVg               (note : ρ = m/V  )
                                             
Thus     Fb     =   ρ V g

Where  Fb   =  Bouyant Force or Upthrust
             ρ     =  Density of fluid
            V     =  Volume of fluid displaced or the volume of the object that immersed in the fluid.


Equation for buoyant force

1. Buoyant force = Weight of fluid displaced
2. Buoyant force = ρVg
3. Buoyant force = Weight object in air – weight in water